K. Rutherford, D. Doerffel (2002)  In: 14th International Symposium on Unmanned Unthetered Sumersible Technology, 2002, Durham, New Hampshire.

Lithium polymer cells are an attractive energy source for underwater vehicles due to heir high specific energy and possible operation at hydrostatic pressure. Their behaviour at pressures experienced in the deep ocean is of particular concern to designers. This paper presents test results that show how the voltage during discharge is affected by temperatures between 4°C and 28°C, and pressures of 0.1 MPa and 60 MPa. A simple non-linear equivalent circuit to model the internal resistance of the cell is shown and the effect of temperature on resistance is found. The main conclusions are that lithium polymer cells can operate at 60 MPa, and their performance is similar to that at 0.1 Mpa. Underwater cold temperature and high current reduce the performance of the cell more than high pressure.

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